There have been many attempts to increase the efficiency of motorized vehicles and thereby decrease the harm to the environment. One method has been to supply heated air to an intake manifold. The following patents describe the known methods for supplying heated air to the intake manifold of an engine.
U.S. Pat. No. 1,376,294 relates to an air intake system for internal combustion motors. The air intake system includes a pipe which is used to draw hot air from around the engine, in particular the exhaust manifold, and introduce the hot air into the intake manifold. If the engine gets too hot, the pipe can be turned to draw cool air from the fan until the engine is cooler. This intake system has the drawback that hot air from the exhaust manifold is too dry for efficient burning in the engine. Furthermore, this system is unable to react to different supply continuously variable amounts of warm air as the air demands of the engine vary.
U.S. Pat. No. 2,203,407 relates to an air cleaner assembly for a tractor. The air cleaner is combined with the radiator in one piece. The air flows through a conduit over the top of the radiator and into the air cleaner. The intake is shaped such that heavy dust particles pass through the radiator and not into the conduit. The air being supplied to the air intake of the engine has not passed through the radiator.
U.S. Pat. No. 3,085,558 discloses a preheater for carburetor inlet air. The preheater uses coolant from the engine. The preheater is used during the engine warm up cycle to prevent icing.
U.S. Pat. No. 3,473,522 discloses a mechanism for heating air using the exhaust manifold of an engine and the hot coolant.
U.S. Pat. No. 4,365,607 discloses a hot-air intake system of an internal combustion engine. The hot-air intake system uses air heated by the exhaust manifold.
U.S. Pat. No. 4,362,084 relates to a valve for apportioning preheated air and non-preheated air to an internal combustion engine. The valve is operated by a thermostat.
U.S. Pat. No. 4,946,124 discloses a clamp used to transfer hot air from the exhaust manifold to the intake manifold.
U.S. Pat. No. 5,046,473 discloses an automatic air intake temperature regulator apparatus and method. A shutter is opened and closed based on the temperature of the air entering the air intake.
It has now been found that the fuel efficiency of an engine is not only affected by the temperature of the air entering the intake manifold, but also by the amount of moisture in the air. It has also been found that air heated by the exhaust manifold of an engine is usually too hot and dry, and therefore the efficiency of the engine is decreased. Thus, in general air heated by the exhaust manifold has the wrong concentration of gasses, such oxygen and water vapor, for efficient combustion.
The above mechanisms for supplying heated air to the air intake are complicated and expensive. Furthermore, conventional mechanisms do not continuously adjust the amount of heated air based on the air requirements of the engine as the motorized vehicle is operated.
There is a need for an uncomplicated and economical apparatus which is capable of supplying warm air having adequate moisture to the intake manifold of an engine. There is also a need for an apparatus which is capable of continuously adjusting the amount of warm air supplied to the engine based on the air requirements of the engine as the vehicle is being operated.